Experimental Setup For Measurement Research Articles

Feasibility Study of a Piezo Actuator as a Potential Standard in Calibration for Roundness Instruments

The paper presents experimental data that show the possible application of a piezo actuator in the role of calibration standard that can serve as an alternative route to currently available methods like gauge blocks or flick standards. First, the experimental setups for interferometric and roundness instruments measurements were described. Next, the experiments using an interferometer for calibration of the piezo actuator were shown. Finally, the application of a piezo actuator to calibrate the roundness instrument, to state the correction factor for the roundness probe, and to relate it to the unit of metre, assuring the traceability of future measurements was performed. Detailed procedures of simulating grooves and then processing the data were described and the calibration curve was obtained using regression analysis. The estimation of uncertainty provided by different factors during the measurements was given to fulfil as closely as possible real calibration procedures taken up in the measurement laboratories. Finally, the limitations of the presented procedures were presented and discussed.

Experimental setup for direct measurements of spectral directional emissivity from 0° to 80° angles at temperatures as low as 40 °C

In this work, a direct method is developed for measuring the spectral directional emissivity of optically thick materials for temperatures ranging between 40 °C and 450 °C at angles from 0° to ∼ 80°. The direct method consists in measuring and comparing thermal radiation emitted from a sample to that of a blackbody reference source. Emphasis is placed on the importance of accurate calibration when performing measurements at low temperature (<50 °C) and on the assessment of uncertainty, estimated between 2 and 20% in the best and worst configuration respectively. The sample is fixed on a heater mounted on a rotation stage allowing directional measurements. Thermal radiation is collected by an optical setup and sent to a Fourier-transform infrared spectrometer (FTIR) performing spectral measurements in the 2–25 μm range using a room-temperature DTGS detector. Sample, blackbody source and optics are placed inside a black-coated enclosure purged with dry air and equipped with temperature sensors for estimating angle-dependent ambient radiation incident on the sample. As examples to illustrate the capabilities of the setup, directional spectral measurements are performed from normal to 80° on both a SiO2 and an aluminum sample at 100 °C.

Experimental Setup for Measurement of AC Loss in HTS under Rotating Magnetic Field

High-temperature superconducting materials have shown great potential for the design of large-scale industry applications. However, they are complicated under AC conditions, resulting in penalties such as power loss or AC loss. This loss has to be considered in order to design reliable and efficient superconducting devices. Furthermore, when superconductors are used in rotating machines, they may be exposed to rotating magnetic fields, which is critical for the design of such machines. Existing AC loss measuring techniques are limited to measuring under one-dimensional AC magnetic fields or transport currents. Therefore, it is essential to develop and investigate robust experimental techniques to investigate the loss mechanism in HTS machines. In this paper, a new and novel experimental technique has been presented to measure AC loss in rotating magnetic field conditions. The loss under rotating magnetic fields is measured and compared by numerical modeling methods, and the results show a strong correlation with the numerical modeling and show the effectiveness of the experimental setup.

Joule heating and the thermal conductivity of a two-dimensional electron gas at cryogenic temperatures studied by modified 3ω method

During the standard ac lock-in measurement of the resistance of a two-dimensional electron gas (2DEG) applying an ac current I=2I0sin(ωt), the electron temperature Te oscillates with the angular frequency 2ω due to the Joule heating ∝I2. We have shown that the highest (TH) and the lowest (TL) temperatures during a cycle of the oscillations can be deduced, at cryogenic temperatures, exploiting the third-harmonic (3ω) component of the voltage drop generated by the ac current I and employing the amplitude of the Shubnikov–de Haas oscillations as the measure of Te. The temperatures TH and TL thus obtained allow us to roughly evaluate the thermal conductivity κxx of the 2DEG via the modified 3ω method, in which the method originally devised for bulk materials is modified to be applicable to a 2DEG embedded in a semiconductor wafer. κxx thus deduced is found to be consistent with the Wiedemann–Franz law. The method provides a convenient way to access κxx using only a standard Hall-bar device and the simple experimental setup for the resistance measurement.

A new experimental setup for time-resolved measurements of interactions between gas jets and flexible surfaces

The purpose of this study was to present a new setup for time-resolved measurements of the interactions between gas jets and flexible surfaces. Such interactions are dominated by characteristic surface deformations and gas-driven surface waves. Previous works have studied the gas–surface interaction only in a sectional plane but not as a three-dimensional problem. In our setup, surface deformations and waves were generated by the impingement of a supersonic jet on a flexible surface made of a silicon membrane. The inlet pressure of the Laval nozzle was varied from 0.8 bar to 3 bar and the nozzle surface distance was set in the range of 30–120 mm with respect to the flat surface. The entire surface area and its behavior were recorded using a high-speed camera. The evaluation was based on the pixel intensity values of the recorded surface images during the jet impingement. A fast Fourier transformation was applied to the results to determine the dominant frequencies of surface movements in detail. From this, low- and high-frequency events on the surface can be derived. Correlations between the main process parameters, nozzle distance, nozzle inlet pressure and characteristic surface behavior were deduced and mapped.

A Novel Proof of Concept Experimental Setup for Seabed-Pipe Interface Friction Measurements

Abstract Offshore hydrocarbon pipelines operate at relatively high pressures and temperatures. These conditions lead to their expansion and contraction and ultimately result in pipeline buckling or “walking” after multiple cycles of operation. Such movements are typically opposed by the axial resistance of the pipe-soil interface, which has to be accurately evaluated to optimize the engineering performance of the pipelines while minimizing testing and construction costs. To date, different testing techniques have been adopted to evaluate this resistance throughout the pipeline operational life. These include laboratory soil element testing, laboratory model testing, and in situ testing using specialized, complex, and costly devices. Despite being the most reliable testing technique, in situ tests are limited by the very small number of available specialized field equipment, e.g., the Fugro SMARTPIPE and the recently developed “pipe-like” penetrometers, both of which suffer from some drawbacks related to high costs, practicality, and testing conditions. This paper presents an attempt at addressing most of the limitations that were identified in the currently available methods, leading to the development of a new in situ, cost-effective apparatus for measuring axial pipeline resistance. A laboratory proof of concept experimental setup that could be adapted in future work to become an autonomous field apparatus was designed, produced, deployed on a clay bed and tested under normal stresses in the low-pressure range. The prototype reliably captured the effects of normal stress on the drained interface resistance. It produced accurate interface friction factors that are comparable to those obtained from the direct shear tests on the same soil and interface. The results obtained are very promising and confirmed the practicality and functionality of the proposed prototype. Some areas of improvement that would enhance the efficiency and reliability of the test were identified and will be applied to future versions of the device.

Oscillations for active sensing in olfaction: bioinspiration from insect antennal movements

Crustacean and insect antennal scanning movements have been postulated to increase odorant capture but the exact mechanisms as well as measures of efficiency are wanting. The aim of this work is to test the hypothesis that an increase in oscillation frequency of a simplified insect antenna model translates to an increase of odorant capture, and to quantify by how much and through which mechanism. We approximate the antennal movements of bumblebees, quantified in a previous study, by a vertical oscillatory movement of a cylinder in a homogeneous horizontal flow with odorants. We test our multiphysics flow and mass transfer numerical model with dedicated experiments using particle image velocimetry. A new entire translating experimental measurement setup containing an oil tank enables us to work at appropriate Strouhal and Reynolds numbers. Increasing antennal oscillating frequency does increase the odorant capture rate, up to 200%, proving this behavior being active sensing. This result holds however only up to a critical frequency. A decrease of efficiency characterizes higher frequencies, due to molecules depletion within oversampled regions, themselves defined by overlaying boundary layers. Despite decades of work on thermal and mass transfer studies on oscillating cylinders, no analogy with published cases was found. This is due to the unique flow regimes studied here, resulting from the combination of organ small size and low frequencies of oscillations. A theory for such flow regimes is thus to be developed, with applications to fundamental research on animal perception up to bioinspired olfaction.

Direct Accessibility of the Fundamental Constants Governing Light-by-Light Scattering.

Quantum field theory predicts that the vacuum exhibits a nonlinear response to strong electromagnetic fields. This fundamental tenet has remained experimentally challenging and is yet to be tested in the laboratory. We present proof of concept and detailed theoretical analysis of an experimental setup for precision measurements of the quantum vacuum signal generated by the collision of a brilliant x-ray probe with a high-intensity pump laser. The signal features components polarized parallel and perpendicularly to the incident x-ray probe. Our proof-of-concept measurements show that the background can be efficiently suppressed by many orders of magnitude which should not only facilitate a detection of the perpendicularly polarized component of the nonlinear vacuum response, but even make the parallel polarized component experimentally accessible for the first time. Remarkably, the angular separation of the signal from the intense x-ray probe enables precision measurements even in the presence of pump fluctuations and alignment jitter. This provides direct access to the low-energy constants governing light-by-light scattering.

Quantitative measurement of birefringence in transparent films across the visible spectrum

Common transparent polymer films, such as cellophane and household tape, are frequently used as examples of birefringent materials in textbooks and classroom demonstrations. Qualitatively, birefringence is often demonstrated by layering such films between crossed-polarizers. In this work, we describe an inexpensive experimental setup for the quantitative measurement of birefringence in common household films, suitable for senior high school or undergraduate labs. Whereas traditional approaches for polarization-based classroom experiments typically use monochromatic laser light, we encourage the combined use of an incoherent incandescent light source and a portable spectrometer. In addition, we demonstrate how any concomitant thin-film interference effects can be used to separately measure the optical thickness in the most heterogeneous and uniform films. Such measurement can then be used as an independent experimental confirmation of either the film's index of refraction or its thickness, given knowledge of the other. In an effort to provide examples for the data analysis procedures as well as to investigate a range of materials, we measure the birefringence across the visible spectrum of six common household polymer films, including thin kitchen wrap, cellophane, gift basket film, and common adhesive tapes.

Elastocaloric-like effect in strain-mediated Mn3SnC/PZT magnetoelectric hetero-composite for solid-state refrigeration

Concerning the part of global warming caused by conventional refrigerant gasses, past decades of research on solid-state cooling technologies based on caloric effects present an attractive alternative with zero-greenhouse gas emission and higher operating efficiency. However, the search for materials with large caloric effects near room temperature has become a challenge in modern material physics. Mn-based antiperovskite compounds are favorable caloric materials which generate a reversible enthalpy change by applying an external field. We report a novel approach of piezo-enhanced elastocaloric-like effect on Mn3SnC for solid-state refrigeration application. In the as-designed Mn3SnC/PZT magnetoelectric hetero-composite, the reversible caloric effect of Mn3SnC was regulated by the electric field-induced strain in the PZT piezoelectricity layer without any external magnetic field. In addition, we proposed an experimental setup for the direct adiabatic temperature change measurement of the caloric effect. The adiabatic temperature change is as high as ∼ 0.57 K at 280 K under an electric field of 0.8 kV/cm, which is approximately 2 factors larger than that of the magnetocaloric effect value of Mn3SnC under 3 T. By adopting the first-principles theory, we estimated the entropy change is approximately 2.6 J Kg−1 K−1 at 280 K which is close to the previous reports. This work demonstrates a novel approach to effectively enhance reversible caloric effects in first-order phase transition materials via electric fields.

Design and development of an automated experimental setup for ion transport measurements.

The ion transport measurements using various ion-exchange membranes (IEMs) face several challenges, including controllability, reproducibility, reliability, and accuracy. This is due to the manual filling of the solutions in two different reservoirs in a typical diffusion cell experiment with a random flow rate, which results in the diffusion through the IEM even before turning on the data acquisition system as reported so far. Here, we report the design and development of an automated experimental setup for ion transport measurements using IEMs. The experimental setup has been calibrated and validated by performing ion transport measurements using a standard nanoporous polycarbonate membrane. We hope that the present work will provide a standard tool for realizing reliable ion transport measurements using ion-exchange membranes and can be extended to study other membranes of various pore densities, shapes, and sizes.

Remote laser fluorescence method for oil leak detection at an excitation wavelength of 266 nm

Subject of study. The possibility of implementing a remote laser fluorescence method to detect oil leaks on the Earth’s surface at a fluorescence excitation wavelength of 266 nm was analyzed and substantiated. Method. Laser-induced fluorescence spectra of clean oil, oil spilled on different types of soil at different time intervals after leakage, and natural and anthropogenic terrain elements were investigated. The experimental setup for remote measurements of laser-induced fluorescence spectra of oil pollution on the Earth’s surface using a laser source with a wavelength of 266 nm, pulse energy of 0.3 mJ, and a single spectral channel of a detector with a central wavelength of 510 nm and a bandwidth of 84 nm is described. The detection possibility of oil pollution against a background of natural vegetation (shrubs and grass) and soil without oil pollution were investigated remotely at a distance of 75 m using emission with a fluorescence excitation wavelength of 266 nm. Main results. Laser-induced fluorescence spectra of commercial oil from the Ryazan oil refinery and oil from Almetyevsk oil field were obtained in addition to the fluorescence spectra of vegetation, soil, and asphalt. Analysis of the data in laser-induced fluorescence spectra indicates that the maximum of the oil spectra is in the range 450–550 nm. Laser-induced fluorescence from vegetation is the largest interference signal in the detection of oil leaks on the Earth’s surface. Remote detection of oil pollution against the background of vegetation and other landscape elements was experimentally demonstrated both immediately after pollution and two days later. Practical significance. The possibility of remote monitoring of oil pollution on the Earth’s surface was experimentally demonstrated at a fluorescence excitation wavelength of 266 nm at distances close to safe aircraft flying altitudes.

Pulsed Townsend measurement of electron swarm parameters in C4F7N–CO2 and C4F7N–N2 mixtures as eco-friendly insulation gas

Recently, C4F7N mixtures have attracted attention as a promising SF6 alternative due to their low global warming potential and excellent electrical performance. In this study, we introduce a newly built experimental setup for pulsed Townsend measurements as well as the physical model for the acquisition of electron swarm parameters. The effective ionization rate coefficients, electron drift velocity, and density-normalized longitudinal diffusion coefficients in C4F7N and its mixtures with CO2 and N2 were obtained. The reduced critical electric field for pure C4F7N at 100 Pa is determined to be 1002 Td, while it decreases with increasing pressure because of the effect of ion kinetics during the discharge process. C4F7N shows good synergism with CO2 and N2. To have a dielectric strength equivalent to that of SF6, the mixing ratio of C4F7N in its mixtures with CO2 and N2 should be 18% and 12%, respectively. The results provide fundamental data for modeling discharges in C4F7N and its mixtures.

Analysis of the cooling lubricant flow during ejector deep hole drilling by in-process volume flow and pressure measurements

Ejector deep hole drilling is required for a variety of drilling applications with length-to-diameter-ratios larger than l/D > 10 and high quality demands, e.g. on roundness, diameter accuracy and surface quality. The ejector effect is essential for the process and decisive for a stable ejector deep hole drilling process by supplying the working zone with cutting fluid. In order to realize an enhanced fundamental understanding of the ejector effect with its process-typical specialties, a demanding experimental setup for in-process fluid volume flow measurement is developed. On the basis of the resulting deeper process understanding of the cooling lubricant behavior during ejector deep drilling, new optimization strategies for increasing deep hole drilling efficiency in the industry can be achieved.

Advanced experimental setup for in-process measurement of thermo-mechanical load and tool wear when drive shaft turning

The acting thermo-mechanical load during metal cutting and the resulting tool wear influence significantly the surface integrity and thus thecomponent functionality. Therefore, in-process measurement of such process variables is a key strategic approach for monitoring of cutting operations. This manuscript presents a new experimental setup implementing a digital microscope camera and different sophisticated sensors for an automatic measurement of cutting force, temperature, tool wear, acoustic emission and magnetic Barkhausen noise during turning operations. To check the proposed test setup, turning tests on drive shafts from steel 42CrMo4 are performed. The analysis and correlation of the measured process variables with surface integrity parameters show the suitability and robustness of the developed experimental setup.

Experimental setup for thermal conductivity investigation of amorphous materials

Experimental setup for the thermal conductivity measurement of amorphous solids with the glass transition temperature below 250 K is presented. This setup allows to heat the specimen to the melting point and then cool it fast to the glass transition temperature. Thermal conductivity can be investigated in the temperature range from 5 K to 300 K. Thermal conductivity of ethanol in amorphous and polycrystalline states was measured for the verification of the setup function. The results of the measurements agree well with those presented in literature.

Micro-electrochemical Analysis of Pit Initiation at Inclusions of Martensitic Stainless Steel

Martensitic stainless steels are widely used for various machine parts because of their excellent mechanical properties. However, pitting corrosion sometimes occurs in chloride solutions such as seawater. Understanding the mechanism of pit initiation is required. In this study, a micro-electrochemical system equipped with an optical microscope [1] was applied to the real-time observation of pit initiation of a martensitic stainless steel.Re-sulfurized AISI 420 (Fe-13% Cr-0.3% C-0.02% S) stainless steel was prepared by vacuum melting. To obtain a martensite structure, a heat-treatment was conducted at 1273 K for 5 h in Ar atmosphere, followed by air-cooling. The details of the experimental setup and procedure for micro-electrochemical measurements were described in our previous paper [1-3]. Electrochemical measurements were performed in boric acid-borate buffer solutions (pH 8.0) with and without NaCl at 298 K.Polarization curves of a small working electrode with a MnS inclusion were measured in the boric-borate buffer solution without NaCl. A broad current peak was observed around 0.75 V (vs. Ag/AgCl, 3.33 M KCl). In this potential region, discoloration occurred on the inclusion surface. In the case of a small area without inclusion, no current increase was seen around 0.75 V. Therefore, the increase in current around 0.75 V was due to the dissolution of MnS. During micro-scale polarization in the boric-borate buffer solution with 10 mM NaCl, the inclusion surface was observed to dissolve around 0.73 V, and then the current increased. It was observed that pitting corrosion was generated at the same time as the current increased. The dissolution potential of MnS in AISI 420 was determined to be around 0.7 V in the boric-borate buffer solution at pH 8.0, and it was concluded that the MnS dissolution results in pit initiation.

Investigation of the shear-layer instabilities in supersonic impinging jets using dual-time velocity measurements

Motivated by applications in the propulsion industry, the fundamental study of phase-locked shear-layer instabilities in supersonic impinging jets has been of research interest for long time. While such flows have been experimentally investigated in various research studies using time-unresolved particle image velocimetry (PIV) techniques, the understanding of the shear-layer dynamics is limited, due to the absence of temporal information. Time-resolved PIV measurements for high-speed flows require a large bandwidth, which is challenging to achieve with the current state of technology. An alternate approach using time-unresolved double-PIV measurements is presented in the current study, which provides multiple samples of dual-time data, depicted in figure 1. Such data can be obtained using two co-visual PIV systems, triggered at a user-selectable time-offset, ∆t. As shown by Sikroria et al. (2020), the application of techniques like dynamic mode decomposition (DMD) on time-unresolved dual-time data provides valuable information about the flow structures governing the shear-layer instabilities. The experimental setup for such measurements in supersonic impinging jets, followed by the determination of the relevant dynamical flow structures from the data, will be presented in the conference.

Spatially-resolved reaction profiles in Fischer-Tropsch synthesis – influence of operating conditions and promotion for iron-based catalysts

The complex reaction mechanism of iron-based Fischer-Tropsch synthesis comprises of manifold primary and secondary reaction pathways. Within this work, an experimental setup for spatially-resolved measurements on promoted iron-based Fischer-Tropsch catalysts is presented, allowing for a general study of the influence of operating conditions and promotion as well as of the influence of secondary reactions on product selectivity. It was found that, depending on catalyst composition, considerable hydrogenation of 1-alcohols and olefins occurs, while no considerable influence of reinitiation of chain growth on product distribution could be found.

A Simple Thermoelectric Effect Setup for Determining the Conductivity Type of Thin Film Materials

In this article, we present a simple and low-cost experimental setup for thermoelectric effect measurements of thin film materials near room temperature, which can be used to determine their conductivity types. Bi <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Te <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and Sb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Te <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> thin films grown by the molecular beam epitaxy technique were used as the tested samples. Their Seebeck coefficients were determined to be (-141 ± 1) μV/K and (39 ± 2) μV/K, respectively, confirming that the former is an n-type material and the latter is a p-type material. A heterostructure composed of Sb2Te3 and Bi2Te3 was characterized by electrical transport measurements. Data fitting was carried out for its current-voltage characteristics with the Shockley diode model and a real diode model proposed by Cataldo et al., and some physical parameters of the heterostructure were extracted, including its ideality factor and saturation current. Based on its rectifying current-voltage behavior, we confirm that the aforementioned heterostructure is a p-n junction, which echoes the contrast in the conductivity types of Sb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Te <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and Bi <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Te <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> as determined by the thermoelectric effect measurements.